230SL engine rebuild advice

[Scottcorvette]

My 1964 230 engine is stripped now and all the measuring etc has been done. It was found to be in generally good condition with only a light amount of wear in the bores, and minimal wear on the crank with light scoring on the first main bearing. There was very light wear on the cam and there was the option of getting the cam reprofiled or replace the cam.

I decided to go with the new cam and ordered the following, all OE:

Pistons and rings at 1st oversize
Cam and rocker arms
Timing chain and guides
Full gasket set

My engine builder will supply the main and rod bearings, he will bore the engine and re grind the crank. As far as I am aware he hasn't stripped the head yet so don't know the condition of cam bearings, valve guides or valves.

He is a very competent machinist and engine builder that I have used for a good number of years and will do a very nice job. My question is what else should I be doing here?

Now on a corvette engine we would just replace everything as a matter of course but then parts are for nothing unlike the Mercedes equivalents. I don't want to skimp on anything with this car but by the same token I am in very deep with this thing already and don't have money to burn. We were going to run with the original oil pump as it looked a very well made piece and looked to be in good shape, having looked at a couple of threads on here I fear this may be a mistake.

There is also talk of replacing the crank gear, if that is the case should all the gears not be replaced?

What else is recommended that I change, should cam towers be replaced as a matter of course with a new cam or can the bearings be changed in the towers? If the bearings look ok do we run with them again or is this a definite no no? What about the chain tensioner?

Are the head bolts stretch bolts or will they go again?

[Benz Dr.]

Cam shafts can be reground if not worn too badly. You will probably want to replace the ball studs and valve guides due to normal wear. I always replace the oil pump. I would have the IP looked at along with the injectors and CSV to make sure nothing is leaking. No sense spending all of that money and then running the engine rich. Cam gears are not too costly but the distributor drive gear is.

I highly recommend that you use a break in additive like Comp Cams in your engine oil for at least 1000 miles or more. You can use that or buy it ready blended at NAPA - Joe Gibs comes to mind.

[stickandrudderman]

Replace ALL of the gears.
Oil pump is easy to change when the engine is in the car so strip it, inspect it, if you think it looks good re-use it and then observe oil pressure when the engine is running again. If it's low or the pump is noisy (you can hear it resonating through the sump) then you can change it then.
I do not use silicone, I use welseal.
Ball studs are €100 each, you want to hope yours are still round.
You will definitely want valve guides & seals.
Cam grinding costs 50% of the price of a new cam which, to me at least, isn't a wide enough margin to warrant the risks.
So, new cam and rockers. (I may be able to save you a few quid on those, it depends on what discount you're getting from mercs). (oops, I see it's too late for that).
Be sure to check small ends and do them if nec.
Cam towers/bearings can be re-used IF THERE'S NO SCORING TO THE BEARING SURFACE OF THE OLD CAM, otherwise you'll have to replace them.
It is, as Dan says, a good idea to have the IP o/hauled but I think you mentioned already that you've sent it off to the USA to get done.
Be sure to strip and clean the cold start injector, they're always blocked.
Check your throttle butterfly for bearing wear.
Have everything balanced. I always have it done to a tolerance of 0.1g (factory standard was 5g!) and makes a very noticeable difference.

[Scottcorvette]

Thanks, I appreciate the input.

I haven't seen the oil pump but my guy says it all looks good. I will look at the cost of a new one. I went over there with a Corvette motor the other day and had a look at the crank gear, I cleaned the cam sprocket and they certainly don't look worn, the teeth are still flat at their peaks, but I will get the prices on these too, and I think I will probably go with Sticks advice and replace the gears and reserve judgement on the pump. When spending thousands on the motor it seems false economy to save hundreds I guess...

I am not sending the IP to the USA now, the customs grief is just not worth it. I got in touch with Fred Pentecost the other week and will send it to him, he said it would pay to leave it until nearer the time it is going to be run so I will do that. I know I have one bad injector as it was dry when removed and the others were wet so I guess I had better brace for that one, and the cold start valve is another story. I guess it had had a problem before, see the picture.

The head is not stripped but I'm sure it will need everything. He will be grinding the crank and fitting new big and little end bearings, the American in me calls them main and rod bearings.

FWIW I tend to use wellseal on most gaskets and permatex on oilpan and transmission oilpan gaskets, if I use permatex I normally just nip the bolts up so that all gasket surfaces are touching and then leave overnight. I torque to specs the following morning, or if the gasket starts to squeeze I leave it there. Works for me most of the time...

[Naj ✝︎]

Hi, Scott,
Do you have a picture of your intake manifold?
That csv is for an early 220 engine (I think) where it was mounted at the back of the manifold.
Normal Pagoda csvs have a double jet and mounted in the middle of the manifold.

Naj

[Scottcorvette]

The CSV has a plastic cover pushed over the jets, I can only assume it was leaking fuel and this was a means of curing it....

Photos of intake.

[Naj ✝︎]

The CSV has a plastic cover pushed over the jets, I can only assume it was leaking fuel and this was a means of curing it....

Photos of intake.

The CSV has a plastic cover pushed over the jets, I can only assume it was leaking fuel and this was a means of curing it....

Photos of intake.

I guess you may have twin jets under the cover

[Scottcorvette]

Mine is like that under the cover. I can only assume it was leaking.

I got a price for the timing gear set, £640 plus vat, and the oil pump is £595 plus vat....that's including discount.

I would really like to see a new gear to compare them to mine but Mercedes Poole don't have any in stock so I don't know if I need to bite the bullet here or not, my engine builder is confident that they will be fine and show very little signs of wear. I probably will replace them for my own peace of mind but just need a bit of time to suck it up. My engine is on hold anyway as we have a couple of Corvette engines that need to be rebuilt first, I don't need mine for ages yet, I just wanted it stripped so I could make sure there was nothing in there that was going to put the kybosh on the rebuild.

I'm resigned to the fact now that this car needs everything and I just have to keep digging deep.